Gas turbine engine components such as buckets, nozzles, and other components in the hot gas path, may be produced in an investment casting process. Generally described, a ceramic core and shell may be produced separately. The ceramic core may be produced by pouring a ceramic slurry into a metal die and solidifying the ceramic material. The ceramic core then may be encased in wax and a ceramic shell may be formed around the wax pattern. The wax that encases the ceramic core then may be removed to form a ceramic mold in which a metallic component may be cast. Once the metallic component is cooled, the shell materials may be stripped away and the ceramic core may be leached away to form the finished product. Other types of component casting methods may be used.
Components having complex geometry such as internal passages and voids therein may be difficult to cast or otherwise created. For example, such complex geometries may include buckets and nozzles with internal airflow passages for cooling. The tooling used for the manufacture of such parts may be expensive and time consuming to create. Moreover, the chemicals used to leach away the ceramic material may be toxic and hazardous to use.